Process for producing 1, 3-dialkyl-2-imidazolidinone

Abstract

An improved process of producing 1, 3-dialkyl-2-imidazolidinones directly from N, N'-dialkylethylenediamine and urea with a high yield is provided, which process comprises reacting a N, N'-dialkylethylenediamine of the formula <IMAGE> wherein R represents -CH3, -C2H5, -C3H7 or -C4H9, with urea at 180 DEG C. or higher in the presence of a polar solvent, to obtain a 1, 3-dialkyl-2-imidazolidinone of the formula <IMAGE> and preferably comprises carrying out the reaction at two stages, that is, the initial period reaction being carried out at 140 DEG C. or lower to from a 1, 1'-dialkyl-1 1'-dimethylenebisurea and successively the latter reaction being carried out at 180 DEG C. or higher.

What we claim is: 
     
       1. In the procedure process of 1,3-dialkyl-2-imidazolidinone expressed by the formula (2) ##STR9## wherein R represents --CH 3 , --C 2  H 5 , --C 3  H 7  or --C 4  H 9 , by reacting a N,N'-dialkylethylenediamine expressed by the formula (1) ##STR10## wherein R is as defined above, with urea, the improvement which comprises carrying out the reaction at a temperature of 180° C. or higher in the presence of a non-protonic polar solvent. 
     
     
       2. In the production process of a 1,3-dialkyl-2-imidazolidinone expressed by the formula (2) ##STR11## wherein R represents --CH 3 , --C 2  H 5 , --C 3  H 7  or --C 4  H 9 , by reacting a N,N'-dialkylethylenediamine expressed by the formula (1) ##STR12## wherein R is as defined above, with urea, the improvement which comprises reacting said N,N'-dialkylethylenediamine with urea in a quantity of twice or less by mol the quantity of said N,N'-dialkylethylenediamine in the presence of a non-protonic polar solvent at a temperature of 140° C. or lower until formation of a 1,1'-dialkyl-1,1'-dimethylenebisurea as an initial period reaction product is completed, and successively raising the temperature up to a temperature of 180° C. or higher at which the latter period reaction is then carried out under pressure. 
     
     
       3. In the production process of a 1,3-dialkyl-2-imidazolidinone expressed by the formula (2) ##STR13## wherein R represents --CH 3 , --C 2  H 5 , --C 3  H 7  or --C 4  H 9 , by reacting a N,N'-dialkylethylenediamine expressed by the formula (1) ##STR14## wherein R is as defined above with urea, the improvement which comprises reacting said N,N'-dialkylethylenediamine with urea in a quantity of about twice by mol the quantity of said N,N'-dialkylethylenediamine in the presence of a non-protonic polar solvent at a temperature of 140° C. or lower until formation of a 1,1'-dialkyl-1,1'-dimethylenebisurea as an initial period reaction product is completed, and successively carrying out a latter period reaction at a temperature of 180° C. or higher while additionally adding said N,N'-dialkylethylenediamine. 
     
     
       4. A process according to claim 1 wherein said 1,3-dialkyl-2-imidazolidinone itself is used as said polar solvent. 
     
     
       5. A process according to claim 2 wherein said 1,3-dialkyl-2-imidazolidinone itself is used as said polar solvent. 
     
     
       6. A process according to claim 3 wherein said 1,3-dialkyl-2-imidazolidinone itself is used as said polar solvent. 
     
     
       7. A process according to claim 1 wherein said 1,3-dialkyl-2-imidazolidinone expressed by the formula (2) is 1,3-dimethyl-2-imidazolidinone. 
     
     
       8. A process according to claim 2 wherein said 1,3-dialkyl-2-imidazolidinone expressed by the formula (2) is 1,3-dimethyl-2-imidazolidinone. 
     
     
       9. A process according to claim 3 wherein said 1,3-dialkyl-2-imidazolidinone expressed by the formula (2) is 1,3-dimethyl-2-imidazolidinone. 
     
     
       10. A process according to claim 2 wherein the molar ratio of urea to said N,N'-dialkylethylenediamine is in the range of 0.6 to 1.2. 
     
     
       11. A process according to claim 3 wherein the quantity of said N,N'-dialkylethylenediamine additionally added in the latter period reaction at a temperature of 180° C. or higher is added so that the quantities of said N,N'-dialkylethylenediamine and urea used in the whole reaction may be nearly equimolar. 
     
     
       12. A process according to claim 1 wherein said reaction temperature is lower than 300° C. 
     
     
       13. A process according to claim 2 wherein said reaction temperature is lower than 300° C. 
     
     
       14. A process according to claim 3 wherein said reaction temperature is lower than 300° C.